Doesn't work for me.
I've been zero carb (literally zero carb) for over a year now.
It worked for a couple of months, and then the hypoglycemia, fatigue and all came back worse than ever. It's done nothing for it, and might have actually made it worse for me.
I've also had significant periods of time with seriously disturbed heart rhythms, although those have been gone for 8-9 months or so, thank god.
I think, in a normal healthy person, keto diets are optimal. But the adrenal glands are called on for the conversion of proteins and fats into the minimum glucose needed, and if they are messed up you're going to have issues either.
High cortisol will prevent you from burning fat primarily because the cortisol will raise your sugars too high, which will spike insulin which turns off fat burning and promotes fat storage.
Low cortisol will prevent you from burning fat/protein properly as well because it is one of the hormones essential for gluconeogenesis to occur.